Out-Of-Phase Speakers

[highfigh]

As mentioned above, 8 ohms is 8 ohms. This is the DC impedance of the speaker and will be the same which ever polarity you hook up the ohm meter. Just to be back up my statement with a measurement, I put my DMM on my Polk RT-800i (two way speaker, one tweeter, two low range speakers) and confirmed the same DC impedance both ways. The good thing about this is that you can't damage your amplifier by connecting "backwards", the amp will have the same DC load either way. Remember, the signal to the speaker is AC, so if the DC impedance were polarity dependent, I think the results might be strange with the different current that would result on each phase of the signal, i.e. if the positive excursions drew more current than the negative excursions.

If we talk about AC impedance, which will vary with frequency, then there is no polarity, so the question is moot.

Now, having said all that, this doesn't necessarily mean that the speakers will sound the same with either polarity connection. I think the differences will be very subtle, but it is possible there will be differences. One reason could be if any polarized components are used in the crossover networks, not likely, but possible. Also, circuits tend to be built with grounds as planes or shields, so connecting the active signal to the such a ground in the circuit could have unexpected effects. There could be other things that make differences in each particular crossover network or speaker. I expect that the differences would beyond what my ear could distinguish, but I'm sure there are those who could.

Since I don't know what is in my speaker without ripping it apart, I always connect my speakers with the "correct" polarity, but if you want to experiment on your own, you shouldn't need to worry about damage to your amp when you try it.

DC and impedance don't go together. Impedance is resistance to alternating current.

 

[highfigh]

.....Midcow, killer post with lots to look at, but I'm not talking phase-control for bass-seperates....I really appreciate all responses, but, once again, must hear to understand.....

.....my front soundstage has 2 or 5 times more realism than before, but how do you measure that?.....

Bottom line- if you like it, great but I can pretty much guarantee that when the music was mastered, it wasn't wired that way so what you're calling realism is completely different from what they heard. What they heard is the most realistic representation of the music but the way music is mixed and even stereo is just an illusion. The instruments weren't located in their apparent positions unless it was a live recording and they wanted to make it sound as close to the event as possible so 'realism' is hard to nail down. When it sounds really good- that's the prize.

As I posted before, changing the polarity of the speakers does make it sound completely different and in some cases better, because of the room's acoustics. We can't all have perfect listening rooms but being happy with the sound of the system is the end goal.

 

[mulester7]

Bottom line- if you like it, great but I can pretty much guarantee that when the music was mastered, it wasn't wired that way so what you're calling realism is completely different from what they heard. What they heard is the most realistic representation of the music but the way music is mixed and even stereo is just an illusion. The instruments weren't located in their apparent positions unless it was a live recording and they wanted to make it sound as close to the event as possible so 'realism' is hard to nail down. When it sounds really good- that's the prize.

As I posted before, changing the polarity of the speakers does make it sound completely different and in some cases better, because of the room's acoustics. We can't all have perfect listening rooms but being happy with the sound of the system is the end goal.

.....Bravo, HighFigh....must hear to understand.....

 

[highfigh]

.....Bravo, HighFigh....must hear to understand.....

It's all in the ear of the behearder/holder, thingy.

I finally put the analyzer on my speakers- did it with the 6.5" 2-ways I normally listen to and true to form, I just had to take it off the stand and decide to re-do the crossover and swap the tweeter for one of the new ones I bought. The crossover had a Zobel and when I built them, they were completely different drivers, although they're still Peerless. The crossover points are OK but I want to smooth out the impedance curve. Now I want to build new cabinets and crossovers.

Anyway, there was no difference in impedance/phase curves and the parameters stayed the same. I don't have an SPL meter but if the Z didn't change, the SPL shouldn't.

What a hobby- just can't leave well enough alone.

 

[mulester7]

Anyway, there was no difference in impedance/phase curves and the parameters stayed the same.

.....Great, HighFigh, thanks for doing that test....I figured out what's going on late this afternoon....remember that 1-2-3 instead of 3-2-1 thing?....here's what I believe's happening....the full-range signal is going to both elements of a 2-way speaker if the crossover is entered through the negative side by the plus wire....think about it....the full-range signal goes through the woofer and "then", the signal goes negatively through the components of the passive crossover meant to affect the signal if 1-2-3 were being done....in like manner, the tweeter get's the full-range signal also.....

.....not as much volume is needed from the surrounds compared to the mains and center....I have seen nothing is at risk, unless you suddenly twisted the overall volume knob two rounds, and that would most-likely harm speaker elements no matter how they were wired.....

.....so it's not a game of impedances, huh?....that's the "efficiency" I heard, full-range coming through both elements....and, any way you slice it, it will stay in my system....comments?.....

 

[mulester7]

.....yeah, kinda' popped a big bubble for me, too....oh well, at least we were all thinking....my next thread will be on lining your center speaker with raw bacon and fresh apple slices thumb-tacked to the inside walls....a rich guy told me to do this, and he said it made a big difference in his sound-quality....coming soon!.....

 

[Alex2507]

Bacon ???

 

[mulester7]

.....my next thread will be on lining your center speaker with raw bacon and fresh apple slices thumb-tacked to the inside walls.....

.....you Guys go ahead and work your center speakers "now" as best you can, and you'll be far ahead when the thread breaks.....

 

[mulester7]

Bacon ???

.....gives a smokey quality to the music....eventually.....

 

[Alex2507]

.....gives a smokey quality to the music....eventually.....

Speaking of lining the inside of your speakers with something, you might enjoy this:

http://forums.audioholics.com/forums/showthread.php?t=46286

It's my first time at bat for show and tell.

 

[mulester7]

Speaking of lining the inside of your speakers with something, you might enjoy this:

http://forums.audioholics.com/forums/showthread.php?t=46286

It's my first time at bat for show and tell.

.....Alex, those speakers look great as per the damping material....are they part of your current front soundstage?.....

 

[Alex2507]

These are my current speakers. This hobby has such extremes that it's nuts. I have since bought another matching sub which is pretty much plenty for a condo. I say this in every other post that I post but I shut them off in the evening. When I play 2 channel music I run the audio through an old EQ/RTA that I set up with some test tones. I must have spent 40 hours easy messing around with that and I'm still not sure that I have it right. I certainly enjoy myself even though I'm just scratching the surface.

 

[mulester7]

I'm still not sure that I have it right. I certainly enjoy myself even though I'm just scratching the surface.

.....just got back, Alex, sorry.....

.....Alex, if your speakers really sound good to you, it's probably right....if you get chill-bumps every now-and-then, your speakers please you....

 

[Midcow2]

.....Alex, a couple of years ago, I ran a pair of my current floorstanders up front, and a pair of my current same-line bookshelves as 4-corner, with all four speakers intentionally cross-wired for 4-5 months....at the time, that was my only system....might have been 6-7 months, not sure, and I kicked the four speakers worth an honest $5700 virtuallly every day with Crown K2's....LOUD levels....marvelous amp....have three on my bottom-seperates....anyhow, after let's say about 6 months, what started getting to me was the highs, as a bit of raspiness crept in I noticed increasingly for a week or so....I then reversed the cross-wiring, and all I could say is it sounded better, I guess, as per no raspy initially, but the inner-detail wasn't as good, either....yes....the 4 speakers when they were cross-wired lost some low-end, but the low cycles were still there.....

.....long story short, I had 2 SVS B-4's to keep the cross-wiring warm, and I got tired of "direct cross-wiring sound" coming from the front soundstage, soooo, I had to miss the effect....until about a month ago.....

.....I'll quit here until we get a measurement of the impedence of an 8-ohm speaker cross-wired out-of-phase being driven.....

Mulester,

Very nice set-up . Maybe you are just getting more in tune to sound. This is probably a dumb question, but have you equalized the speaker DB levels with an SPL meter? I ran Audyssey on my system as a starting point, then I ran an SPL meter and now I love the sound. I equalized all speakers, except for the SVS sub which I boosted about 10 dB

Later,

MidCow2

 

[highfigh]

.....Great, HighFigh, thanks for doing that test....I figured out what's going on late this afternoon....remember that 1-2-3 instead of 3-2-1 thing?....here's what I believe's happening....the full-range signal is going to both elements of a 2-way speaker if the crossover is entered through the negative side by the plus wire....think about it....the full-range signal goes through the woofer and "then", the signal goes negatively through the components of the passive crossover meant to affect the signal if 1-2-3 were being done....in like manner, the tweeter get's the full-range signal also.....

.....not as much volume is needed from the surrounds compared to the mains and center....I have seen nothing is at risk, unless you suddenly twisted the overall volume knob two rounds, and that would most-likely harm speaker elements no matter how they were wired.....

.....so it's not a game of impedances, huh?....that's the "efficiency" I heard, full-range coming through both elements....and, any way you slice it, it will stay in my system....comments?.....

A tweeter can't see a full-bandwidth signal if it has any kind of passive high pass filter, it always has at least a capacitor in series. Also, since many have a 12dB/octave filter, the inductor shunts lower frequencies before they would ever get to the tweeter. Likewise, a mid has a bandpass filter and a woofer has a low pass filter in front of it. Because music is AC signal, any component in series will work the same before or after the driver. They're just placed ahead of the speakers because a 2nd order (or higher) needs to be a complete network before it gets to the load. Placing the load between the filter components changes the frequency each will affect (high pass determined by F=1/(2ΠCR)). An inductor after a cap and load will react differently from being placed between the cap and load.

Here's some additional information on this:
http://www.pac-audio.com/crossover/crossover.asp
and http://en.wikipedia.org/wiki/Audio_crossover

 

[mulester7]

A tweeter can't see a full-bandwidth signal if it has any kind of passive high pass filter, it always has at least a capacitor in series. Also, since many have a 12dB/octave filter, the inductor shunts lower frequencies before they would ever get to the tweeter. Likewise, a mid has a bandpass filter and a woofer has a low pass filter in front of it.

.....but we're not doing 1-2-3, HighFigh.....

Because music is AC signal, any component in series will work the same before or after the driver.

.....so the signal goes back through the driver again after going through a high-pass filter or coil as we employ 3-2-1 by cross-wiring?....I can't see that one....

 

[ski2xblack]

.....but we're not doing 1-2-3, HighFigh..........so the signal goes back through the driver again after going through a high-pass filter or coil as we employ 3-2-1 by cross-wiring?....I can't see that one....

I still don't think this has anything to do with what you're hearing...as stated in a previous post, a crossover in series in an AC curcuit effects the signal regardless.

You have your rears out of phase with your fronts, with them each consistent with regards to each other, correct? This reminds me of the old so-called Hafler-Dynaquad matrixing shceme, in which the rears were also intentionally out of phase (pos output on amp wired to neg input on rears) in relation to the fronts. Given your discreet rear channels of a modern 5.1 setup, the interactions of out of phase rears with the fronts is hard to predict, but certainly more complex than in the rudimentary matrix described above, and it may explain some of the pleasant and novel aural experiences you're having. I can easily see how it could produce the effects you are describing; depending on the content of the rear channels, the effect on your front soundstage could be quite dramatic.

 

[ski2xblack]

.....but we're not doing 1-2-3, HighFigh..........so the signal goes back through the driver again after going through a high-pass filter or coil as we employ 3-2-1 by cross-wiring?....I can't see that one....

Think of the 'driver-3-2-1' and '3-2-1-driver' as singular parts of the circuit...they don't behave differently one direction or the other...filters still filter, drivers still produce whatever is unfiltered...does this help?

 

[highfigh]

.....but we're not doing 1-2-3, HighFigh..........so the signal goes back through the driver again after going through a high-pass filter or coil as we employ 3-2-1 by cross-wiring?....I can't see that one....

Could you explain what 1-2-3 and 3-2-1 are? I must have missed something.

The signal isn't flowing like water. When signal is present, it's basically just circuit resonances. Sound, on the other hand, starts at the source and moves through the medium and continues until it hits a boundary to be reflected, absorbed or diffused.

If a cap or coil is in series, the signal goes through both and there's no way to bypass it. If the crossover is a 2nd order (or higher), the coils or caps parallel to the rest of the circuit are still in the same position to act on the signal.

 

[mulester7]

I still don't think this has anything to do with what you're hearing...as stated in a previous post, a crossover in series in an AC circuit effects the signal regardless.

.....Ski, I appreciate very much what you've posted, especially the last part....but, humor me....please play "follow the signal" from the amp's positive output back to the amp's negative input traveling through the crossover leads backwards....any components of the crossover that affects the signal, are being gone through AFTER the signal goes through the speakers' speaker elements....no?.....